1. Field of the Invention
This invention relates to a time set apparatus for an electronic clock, particularly to an improvement of a time set part of a digital clock which is widely adapted for a purpose of, e.g., a timer of audio equipment, VTR, TV and the like.
2. Prior Art of the Invention
An electronic digital clock having a function of timer, alarm, etc. is now widely marketed. Moreover it is often combined with home use electrical manufactures such as radio receivers, audio components, VTR or TV, or any other industrial instruments.
In such electronic digital clock the present actual time is displayed at a display window, whereas a set time for alarm or timer is displayed at the actual time display window or at some other display provided only for the set time.
A correction on the displayed actual time or on the set time is carried out by means of a switch which is used both for the actual time correction and the set time correction, or it is carried out by means of an actual time correction switch and a set time correction switch.
For correcting the time there are some manners in which putting forward or putting back the displayed time is made by one switch or two independent switches and in which the time correcting speed can be changed from slow to fast. In any case it is necessary to manipulate one or two switch keys (buttons) with monitoring the displayed time so as to set the clock to a desired time.
According to a prior art electronic clock, during a time correction, a person who wishes to correct or change the time has to carefully manipulate a time correction key while looking at the display to determine whether or not the time displayed reaches the desired corrected or changed time. Especially, when the user is not yet skilled on the time change manipulation, some difficulties are imposed.
A typical prior art arrangement addressing the above problem is Japanese Patent Application Publication No. 56-35391. This Publication discloses a time set apparatus comprising twelve switch keys being circularly arranged like the display board of a conventional analog type clock. In this apparatus the time set is carried out by the manipulation of twelve keys.
The operation panel for manipulating the time keys of the above prior art has a configuration similar to the configuration as shown in FIG. 1. Thus, there are provided with a display window 10 in which present actual time etc. are displayed, with an hour set key array 11 being formed of twelve switches h1 to h12, and with a minute set key array 12 being formed of twelve switches m0 to m55. The arrangement of key arrays 11 and 12 resembles the arrangement of numbers of an analog clock face.
In such prior art electronic clock arrangements the time set manipulation will be performed as follows.
Assume here that the time "10:30" is to be set in an alarm set mode or an actual time set mode. In this case the switch h10 of hour set key array 11 and the switch m30 of minute set key array 12 are depressed. Such depressing manipulation is simpler and easier than a manner in which the desired set time is reached through the manipulation of a fast time scanning or the dialing of a time scale.